96 DUDLEY MEMORIAL VOLUME 



3. Picea. Spruce. 

 Trees with spreading or sometimes pendulous branches. Leaves linear, 

 flat or 4-sided, spirally arranged, sometimes appearing 2-ranked, not nar- 

 rowed into a leaf-stalk ; leaf -scars raised on prominent woody pedicels, which 

 give the twigs a decided roughness after the leaves have fallen. Cones pen- 

 dulous, their scales persistent, completely concealing the very short bracts. 

 The eighteen known species are confined in their distribution to the north 

 temperate and subarctic regions. 

 Leaves quadrangular with stomata on all 4 sides. 

 Cone-scales rounded at apex. 



Leaves J^-% inch long, obtuse; branchlets not long-pendulous. 

 Young twigs glabrous; cones 1J4-2 inches long. 



1. P canadensis. 

 Young twigs pubescent; cones 3-5 inches long. 



2. P. orientalis. 

 Leaves 1J4-2 inches long, sharp-pointed. 3. P. Smithiana. 



Cone-scales not rounded at apex; leaves acute or sharp-pointed. 



Leaves dark green, abruptly acute; cone-scales firm on the margins, 



truncate at apex. 4. P. excelsa. 



Leaves blue green, acuminate and callous-tipped ; cone-scales rhomboidal, 

 their margins flexuose. 5. P- Parry ana. 



Leaves flattened, with 2 silvery bands of stomata above. 



6. P. sitchensis. 



1. Picea canadensis (Mill.) B. S. P. White Spruce. 



Leaves spreading from all sides of glabrous twigs, J4-^ inch long, 1/24 

 inch wide, sharp-pointed, dull glaucous green ; flowers pale red or yellowish ; 

 cones \%.-2 inches long, about 1 inch broad; scales rounded at apex, Yi inch 

 wide. 



A tree 50-150 feet high, with a symmetrical pyramidal head. Native of 

 north temperate and subarctic America, extending from Alaska to Labrador 

 and from Montana to New England. One tree is near the center of the 

 Cactus Garden. 



2. Picea orientalis (L.) Carr. Caucasian Spruce. 



Leaves spreading from all sides of the pubescent twigs, J^-j4 inch 

 long, 1/12 inch wide, 4-sided, blunt at apex, dark lustrous green; flowers 

 carmine; cones 3-5 inches long, about 1J4 inches broad; scales rounded at 

 apex, Ys iiich wide. 



Native of the Caucasus and Asia Minor. Two trees are near the center 

 of the Cactus Garden. 



